Method for eliminating burrs generated in PD optical signal voltage conversion process

Abstract

The invention relates to the technical field of medical detection, in particular to a method for eliminating burrs generated in the PD optical signal voltage conversion process, and the method comprises the steps: carrying out the high-frequency noise and AC component filtering of an input signal through a capacitor C4; the transimpedance amplifier amplifies the filtered input signal; the first pi-type RC filter filters high-frequency noise and alternating-current components of the amplified input signal; the buffer circuit processes the filtered input signal; and the pi-type RC filter II filters high-frequency noise and alternating-current components of the processed input signal. A circuit processing part and an algorithm processing part are used. An electric signal converted from a PD optical signal is received through a circuit, certain burrs are eliminated, and then the electric signal is transmitted to an IC for collection. And the processor performs summation and then averaging on each data acquired by the IC and previous data, so that the influence of burrs is eliminated, and the problem that the influence of burr signals on a detection result is relatively large is solved.

Description

Technical Field

[0001] The present invention relates to the field of medical detection technology, and in particular to a method for eliminating burrs generated in a PD optical signal voltage conversion process. Background Art

[0002] In the field of medical testing, turbidimetry is one of the common methods for detecting the concentration of specific proteins in body fluids. During the test, the specific protein in the sample reacts with the specific reagent, and the turbidity of the reaction mixture changes. The change in turbidity is detected by optical methods, and the concentration of the specific protein in the sample can be obtained through algorithm calculation. The optical method involves the emission of LD light and the reception of PD light signals. The reception of PD light signals requires the light signal to be converted into a voltage signal, which is then transmitted to the processor for quantification. In the process of photoelectric conversion, due to the influence of internal factors of the detection system or the factors of the transmission medium, burr interference signals that are not conducive to the result judgment are often generated. Especially when the sample protein concentration is low, the burr signal has a greater impact on the test results. Therefore, eliminating the burrs generated in the voltage conversion process of the PD light signal is one of the key difficulties of this type of detection method.

[0003] Glitch signals are irregular jump spike signals. If they are not effectively processed, they will affect the accuracy and stability of detection. In the early stage of the detection system design, excellent PCB layout and anti-interference of signal transmission lines are the basis for stable and accurate collection of PD optical signals. Designing these two points well will greatly reduce the probability of glitch signals. Based on the idea of ​​danger and the viewpoint of ensuring system margin, assuming that glitch signals are inevitable, in order to ensure that the detection system can still operate normally when glitch signals appear, the glitch generated after the PD optical signal is converted into an electrical signal must be eliminated before data analysis. Summary of the invention

[0004] The purpose of the present invention is to provide a method for eliminating burrs generated in the process of voltage conversion of PD optical signals, aiming to solve the problem that the burr signal has a great influence on the detection result.

[0005] To achieve the above object, the present invention provides a method for eliminating burrs generated in the process of PD optical signal voltage conversion, comprising the following steps:

[0006] A glitch elimination circuit is established by using capacitor C4, a transimpedance amplifier, a π-type RC filter 1, a buffer circuit and a π-type RC filter 2;

[0007] The capacitor C4 filters out high-frequency noise and AC components of the input signal;

[0008] The transimpedance amplifier amplifies the filtered input signal;

[0009] The π-type RC filter filters out high-frequency noise and AC components of the amplified input signal;

[0010] The buffer circuit processes the filtered input signal;

[0011] The π-type RC filter 2 filters out high-frequency noise and AC components of the processed input signal.

[0012] Among them, in “the transimpedance amplifier amplifies the filtered input signal”, the transimpedance amplifier includes an operational amplifier U1, a capacitor C1 and a resistor R1, the operational amplifier U1 is connected to the capacitor C4, and the capacitor C1 is connected in parallel to the resistor R1.

[0013] Among them, the method for eliminating burrs generated in the voltage conversion process of PD optical signals as described in claim 2 is characterized in that: in "the π-type RC filter one filters out high-frequency noise and AC components of the amplified input signal", the π-type RC filter one includes a capacitor C5, a resistor R2 and a capacitor C2, the resistor R2 is connected to the operational amplifier U1, the capacitor C5 is connected to one end of the resistor R2, and the capacitor C2 is connected to the other end of the resistor R2.

[0014] Among them, the method for eliminating glitches generated in the voltage conversion process of PD optical signals as described in claim 3 is characterized in that: in "the buffer circuit processes the filtered input signal", the buffer circuit includes an operational amplifier U2 and a resistor R4, the operational amplifier U2 is connected to the resistor R2, and the resistor R4 is connected to the operational amplifier U2.

[0015] Among them, in “the π-type RC filter 2 filters out high-frequency noise and AC components of the processed input signal”, the π-type RC filter 2 includes a capacitor C3, a resistor R5 and a capacitor C6, the resistor R5 is connected to the operational amplifier U2, the capacitor C3 is connected to one end of the resistor R5, and the capacitor C6 is connected to the other end of the resistor R5.

[0016] The present invention discloses a method for eliminating burrs generated in the process of voltage conversion of a PD optical signal, comprising the following steps: establishing a burr elimination circuit through a capacitor C4, a transimpedance amplifier, a π-type RC filter 1, a buffer circuit and a π-type RC filter 2; the capacitor C4 filters out high-frequency noise and AC components of the input signal; the transimpedance amplifier amplifies the filtered input signal; the π-type RC filter 1 filters out high-frequency noise and AC components of the amplified input signal; the buffer circuit processes the filtered input signal; the π-type RC filter 2 filters out high-frequency noise and AC components of the processed input signal. The present invention uses circuit and algorithm processing in two parts. The circuit receives the electrical signal converted from the PD optical signal, eliminates certain burrs, and then transmits it to the IC for collection. The processor sums and averages each data collected by the IC and the previous data to eliminate the influence of the burrs, thereby solving the problem that the burr signal has a large influence on the detection result. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0018] Figure 1 This is the schematic diagram of the optical detection principle of turbidimetry.

[0019] Figure 2 This is the schematic diagram of the glitch elimination circuit.

[0020] Figure 3 The present invention provides a flow chart of a method for eliminating burrs generated during a PD optical signal voltage conversion process.

[0021] Figure 4 This is a schematic diagram of the output of an oscilloscope whose input signal is a constant current source.

[0022] Figure 5 It is an ideal data graph.

[0023] Figure 6 It is to add abnormal data graph.

[0024] Figure 7 This is a schematic diagram of the algorithm after processing abnormal data. DETAILED DESCRIPTION

[0025] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0026] See also Figures 1 to 7 The present invention provides a method for eliminating burrs generated in the process of PD optical signal voltage conversion, comprising the following steps:

[0027] S1 establishes a glitch elimination circuit through capacitor C4, transimpedance amplifier, π-type RC filter 1, buffer circuit and π-type RC filter 2;

[0028] Specifically, a glitch elimination circuit is established using the capacitor C4, the transimpedance amplifier, the first π-type RC filter, the buffer circuit, and the second π-type RC filter.

[0029] The capacitor C4 described in S2 filters out high-frequency noise and AC components of the input signal;

[0030] Specifically, the input signal first passes through the bypass capacitor C4 to filter out high-frequency noise and AC components.

[0031] S3, the transimpedance amplifier amplifies the filtered input signal;

[0032] The transimpedance amplifier includes an operational amplifier U1, a capacitor C1 and a resistor R1. The operational amplifier U1 is connected to the capacitor C4, and the capacitor C1 is connected to the resistor R1 in parallel.

[0033] Specifically, the input signal is amplified by a transimpedance amplifier (composed of U1, C1, and R1). C1 and R1 are connected in parallel to help reduce noise and improve circuit stability.

[0034] S4: the π-type RC filter pair filters out high-frequency noise and AC components of the amplified input signal;

[0035] The π-type RC filter 1 includes a capacitor C5, a resistor R2 and a capacitor C2, the resistor R2 is connected to the operational amplifier U1, the capacitor C5 is connected to one end of the resistor R2, and the capacitor C2 is connected to the other end of the resistor R2.

[0036] Specifically, the amplified signal passes through a π-type RC filter (composed of C5, R2, and C2) to filter out high-frequency noise and AC components.

[0037] S5, the buffer circuit processes the filtered input signal;

[0038] The buffer circuit includes an operational amplifier U2 and a resistor R4. The operational amplifier U2 is connected to the resistor R2, and the resistor R4 is connected to the operational amplifier U2.

[0039] Specifically, after being processed by a buffer circuit (composed of U2 and R4), electrical isolation is provided and interference noise between input and output is reduced; input impedance is increased and output impedance is reduced, thereby improving anti-interference capability.

[0040] S6: the π-type RC filter 2 filters out high-frequency noise and AC components of the processed input signal.

[0041] The second π-type RC filter includes a capacitor C3, a resistor R5 and a capacitor C6. The resistor R5 is connected to the operational amplifier U2, the capacitor C3 is connected to one end of the resistor R5, and the capacitor C6 is connected to the other end of the resistor R5.

[0042] Specifically, the output of the buffer passes through a π-type RC filter (composed of C3, R5, and C6) to further filter out high-frequency noise and AC components.

[0043] The circuit is divided into two parts. The first part is composed of the transimpedance amplifier circuit composed of the operational amplifier U1 and the bypass device. Its main function is to amplify the collected small signal for easy collection. The second part is composed of the operational amplifier U2 and the bypass device to form a buffer circuit, which provides high input impedance and low output impedance, can provide electrical isolation and reduce the interference noise between input and output, and has a certain effect on eliminating burr interference. Capacitors C2, C3, C4, C5, and C6 play a greater role in eliminating burrs. The principle is the filtering and compensation effect of capacitors.

[0044] The basic principle of optical detection of turbidimetry is shown in the figure. ① is a laser generator, which is used as a light source during detection. The intensity of the laser can be controlled by adjusting the driving current. ② is an optical lens, which focuses the laser and adjusts the light angle by adjusting the angle of the lens, so that the light passes through the reaction cup, and finally the complete light spot falls on the PD optical signal receiver. ③ is a reaction cup, where the sample and reagent are mixed and reacted. When the turbidity of the reactant in the reaction cup changes, the intensity of the light passing through the reaction cup changes accordingly, and the signal strength obtained by the optical signal receiver also changes accordingly. ④ is a PD optical signal receiver, which is essentially a photodiode, which converts the optical signal into an electrical signal, and then transmits the electrical signal to the subsequent circuit through a wire. ⑤ is a signal processing circuit, which is the application part of the circuit of the present invention. It receives the electrical signal converted by the optical signal receiver, eliminates certain burrs, and then outputs the signal to the IC for collection. ⑥ is IC collection, using an ADC chip to convert the voltage signal into data. ⑦ The processor processes data, which is the processing application of the algorithm of the present invention. The collected data is summed and averaged with the previously collected data to eliminate the influence of the burr signal, and then the processed data is analyzed to obtain the reaction degree and sample concentration of the mixture in the reaction cup.

[0045] The algorithm processing part is located in ⑦, and its principle is:

[0046]

[0047] (x is the data collected at the nth moment, y is the value at the nth moment used for result analysis). The average value of the first n data is used as the nth data for analysis and processing, which is conducive to allocating abnormal data to other locations and improving the smoothness of the data.

[0048] The experimental method is to use Multisim software to simulate the circuit part of the method of the present invention, and to draw graphs of data before and after algorithm processing to demonstrate the effect of the algorithm processing part.

[0049] The state of adding glitch interference is simulated, a constant current source is used to simulate the effective input signal, and a signal generator outputs a square wave with a duty cycle of 1% to simulate the glitch signal and add it to the input signal.

[0050] Depend on Figure 4 It can be seen that the input signal burrs are relatively obvious, while the output signal burrs are basically eliminated after being processed by the circuit part of the present invention.

[0051] Use 100 numerical values ​​increasing in equal proportion to simulate the collected data under ideal conditions, and change the nth one into abnormal data (n is a multiple of 5) to simulate the interference of burrs.

[0052] Depend on Figure 6 and Figure 7It can be seen that after the burr interference is processed by the algorithm of the present invention, the burr is obviously eliminated.

[0053] The above disclosure is only a preferred embodiment of a method for eliminating glitches generated in the PD optical signal voltage conversion process of the present invention. Of course, this cannot be used to limit the scope of rights of the present invention. Ordinary technicians in this field can understand that all or part of the processes of the above embodiments and equivalent changes made according to the claims of the present invention are still within the scope of the invention.

Claims

1. A method for eliminating burrs generated during the voltage conversion process of a PD optical signal, characterized in that: The following steps are involved: A glitch elimination circuit is established by using capacitor C4, a transimpedance amplifier, a π-type RC filter 1, a buffer circuit and a π-type RC filter 2; The capacitor C4 filters out high-frequency noise and AC components of the input signal; The transimpedance amplifier amplifies the filtered input signal; The π-type RC filter filters out high-frequency noise and AC components of the amplified input signal; The buffer circuit processes the filtered input signal; The π-type RC filter 2 filters out high-frequency noise and AC components of the processed input signal.

2. The method for eliminating burrs generated in the voltage conversion process of PD optical signals as claimed in claim 1, characterized in that: In “the transimpedance amplifier amplifies the filtered input signal”, the transimpedance amplifier includes an operational amplifier U1, a capacitor C1 and a resistor R1, the operational amplifier U1 is connected to the capacitor C4, and the capacitor C1 is connected to the resistor R1 in parallel.

3. The method for eliminating burrs generated in the PD optical signal voltage conversion process as claimed in claim 2, characterized in that: In "the π-type RC filter one filters out high-frequency noise and AC components of the amplified input signal", the π-type RC filter one includes a capacitor C5, a resistor R2 and a capacitor C2, the resistor R2 is connected to the operational amplifier U1, the capacitor C5 is connected to one end of the resistor R2, and the capacitor C2 is connected to the other end of the resistor R2.

4. The method for eliminating burrs generated in the voltage conversion process of a PD optical signal as claimed in claim 3, characterized in that: In “the buffer circuit processes the filtered input signal”, the buffer circuit includes an operational amplifier U2 and a resistor R4, the operational amplifier U2 is connected to the resistor R2, and the resistor R4 is connected to the operational amplifier U2.

5. The method for eliminating burrs generated in the voltage conversion process of PD optical signals as claimed in claim 4, characterized in that: In "the π-type RC filter 2 filters out high-frequency noise and AC components of the processed input signal", the π-type RC filter 2 includes a capacitor C3, a resistor R5 and a capacitor C6, the resistor R5 is connected to the operational amplifier U2, the capacitor C3 is connected to one end of the resistor R5, and the capacitor C6 is connected to the other end of the resistor R5.

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